Commands - Functions
Pwd - "Print working directory" - show what dir you're in.
ls - List the contents of a dir.
ls –l - List the contents of a dir and show additional info of the files.
ls –a - List all files, including hidden files.
cd - Change directory.
cd - Go to the parent directory.
file - Determine the type of a file.
cat - Concatenate a file.
less - View text files and paginate them if needed.
Manipulating files and directories
p - Copy a file.
cp –i - Copy a file and ask before overwriting.
cp –r - Copy a directory with its contents.
mv - Move or rename a file.
mv –i - Move or rename a file and ask before overwriting.
rm - Remove a file.
rm –r - Remove a directory with its contents.
rm –i - Ask before removing a file. Good to use with the -r option.
mkdir - Make a directory.
rmdir - Remove an empty directory.
*Essential Keyboard Shortcuts
Switch to the first virtual terminal. In Linux, you can have several virtual terminals at the same time. The default is 6.
Ctrl + Alt + Fn
Switch to the nth virtual terminal. Because the number of virtual terminals is 6 by default, n = 1...6.
Typing the tty command tells you what virtual terminal you're currently working in.
Ctrl + Alt + F7
Switch to the GUI. If you have X Window System running, it runs in the seventh virtual terminal by default. If X isn't running, this terminal is empty.
Ctrl + Alt + +
Switch to the next resolution in the X Window System. This works if you've configured more than one resolution for your X server. Note that you must use the + in your numpad.
Ctrl + Alt + -
Switch to the previous X resolution. Use the - in your numpad.
Paste the highlighted text. You can highlight the text with your left mouse button (or with some other highlighting method, depending on the application you're using), and then press the middle mouse button to paste. This is the traditional way of copying and pasting in the X Window System, but it may not work in some X applications.
If you have a two-button mouse, pressing both of the buttons at the same time has the same effect as pressing the middle one. If it doesn't, you must enable 3-mouse-button emulation.
This works also in text terminals if you enable the gpm service.
Ctrl + Alt + Backspace
Kill the X server. Use this if X crashes and you can't exit it normally. If you've configured your X Window System to start automatically at bootup, this restarts the server and throws you back to the graphical login screen.
Home or Ctrl + a
Move the cursor to the beginning of the current line.
End or Ctrl + e
Move the cursor to the end of the current line.
Alt + b
Move the cursor to the beginning of the current or previous word. Note that while this works in virtual terminals, it may not work in all graphical terminal emulators, because many graphical applications already use this as a menu shortcut by default.
Alt + f
Move the cursor to the end of the next word. Again, like with all shortcuts that use Alt as the modifier, this may not work in all graphical terminal emulators.
Autocomplete commands and file names. Type the first letter(s) of a command, directory or file name, press Tab and the rest is completed automatically! If there are more commands starting with the same letters, the shell completes as much as it can and beeps. If you then press Tab again, it shows you all the alternatives.
This shortcut is really helpful and saves a lot of typing! It even works at the lilo prompt and in some X applications.
Ctrl + u
Erase the current line.
Ctrl + k
Delete the line from the position of the cursor to the end of the line.
Ctrl + w
Delete the word before the cursor.
Shift + PageUp
Scroll terminal output up.
Shift + PageDown
Scroll terminal output down.
The clear command clears all previously executed commands and their output from the current terminal.
Ctrl + l
Does exactly the same as typing the clear command.
If you mess up your terminal, use the reset command. For example, if you try to cat a binary file, the terminal starts showing weird characters. Note that you may not be able to see the command when you're typing it.
When you type the history command, you'll see a list of the commands you executed previously.
ArrowUp or Ctrl + p
Scroll up in the history and edit the previously executed commands. To execute them, press Enter like you normally do.
ArrowDown or Ctrl + n
Scroll down in the history and edit the next commands.
Ctrl + r
Find the last command that contained the letters you're typing. For example, if you want to find out the last action you did to a file called "file42.txt", you'll press Ctrl + r and start typing the file name. Or, if you want to find out the last parameters you gave to the "cp" command, you'll press Ctrl + r and type in "cp".
Ctrl + c
Kill the current process.
Ctrl + z
Send the current process to background. This is useful if you have a program running, and you need the terminal for awhile but don't want to exit the program completely. Then just send it to background with Ctrl+z, do whatever you want, and type the command fg to get the process back.
Ctrl + d
Log out from the current terminal. If you use this in a terminal emulator under X, this usually shuts down the terminal emulator after logging you out.
Ctrl + Alt + Del
Reboot the system. You can change this behavior by editing /etc/inittab if you want the system to shut down instead of rebooting.
Other Essential CLI Related Help Sites:
"Fear is the main source of superstition, and one of the main sources of cruelty. To conquer fear is the beginning of wisdom."
Bertrand Russell (1872 - 1970), Unpopular Essays (1950), "Outline of Intellectual Rubbish"
You may also want to check out our list of Linux terminal emulators.